A man has been arrested on suspicion of arson after a fire at the office of Labour MP Sharon Hodgson.

A blaze broke out at the Washington and Gateshead South MP’s constituency office in Concord, Washington, just after midnight, Tyne and Wear Fire and Rescue Service (TWFRS) said.

The man in his 20s was also arrested on suspicion of criminal damage and remained in police custody, Northumbria Police said.

The spokesperson for Hodgson said she “will not be deterred and will continue to support her constituents”.

Images also show graffiti on the side of the building which reads “328 days blood on your hands,” but it is not clear how recent it is.

“We will not be commenting or speculating while there is an ongoing police investigation, what we are clear on is there is no place for this kind of violence in our society,” the spokesperson said.

“Sharon will not be deterred and will continue to support her constituents in Washington and Gateshead South as she does day in, day out.”

Northumbria Police urged anyone with information to contact the force.

TWFRS sent seven appliances to the fire and no causalities were reported.

Labour councillor Phil Tye, chair of TWFRS, said: “Our thoughts are with everyone affected by this incident.

“I’d like to thank our firefighters and control staff for their dedication and teamwork during what may be a challenging investigation.”

During a question at the House of Commons earlier, Labour MP for Middlesbrough and Thornaby East Andy McDonald said: “I’m sure I speak for the whole House in sending our best wishes to our colleague in Washington and Gateshead South for the appalling fire at her office overnight, and send our very best wishes to her and her staff.”

Foreign Office minister Stephen Doughty said he was not aware of the “terrible instance” but he was “sure the thoughts of the whole House will be with our colleague”.

He added: “I think particularly in light of international events, and the tragic loss of colleagues, this all the more underlines why we must have security and safety to go about democratic debate in this country, whatever our views, in a safe and secure way.”